<!DOCTYPE html>
<html>
	<head>
		<title>A plus B demo</title>
	</head>
	<body>
		<form method=post action=action.php>
			A = <input name=a><br>
			B = <input name=b><br>
			<input type=submit value="A+B=?">
		</form>
	</body>
</html>